1. Field of the Invention
The present invention relates generally to an electrical connector formed from a single sheet of metal, and more particularly, to a Universal Serial Bus (USB) connector that is a serial interface connecting telephones, keyboards and other such peripheral equipment to a computer, the USB connector having improved mechanical stability and rigidity and providing effective protection against electromagnetic interference.
2. Description of the Related Art
To facilitate an understanding of the conventional art, a description will first be given of the relation between the way the generally rectangular-shaped USB connector is fitted to a printed circuit board and the need for efficient use of the limited space available on the printed circuit board itself.
Specifically, positioning the USB connector atop the printed circuit board so that the longer side of the USB connector Is vertical, that is, perpendicular to the surface of the printed circuit board, requires less space for mounting the USB connector on the printed circuit board than a case in which the longer side of the USB connector is horizontal, with the USB connector therefore mounted on the printed circuit board in that horizontal position. As a result, the printed circuit board, which has a limited size, can be utilized more effectively.
However, positioning the USB connector so that the longer side is vertical, that is, vertically mounting the USB connector, though desirable for efficient utilization of the printed circuit board, is less mechanically stable than when the longer side of the USB connector is horizontal and thus directly mounted on the printed circuit board, that is, when the USB connector is mounted horizontally.
Additionally, a force exerted on the USB connector toward the rear thereof when a cable connector is inserted in the USB connector can be very great, requiring heightened mechanical stability of the mounting of the USB connector on the printed circuit board when the USB connector is mounted in such a way that the longer side of the USB connector is vertical, that is, vertically mounted.
Additionally, the cable itself may be accidentally pulled or wrenched in one or another direction, thus straining the connection with the USB connector in a lateral direction as well and possibly loosening the connection of the USB connector to the printed circuit board, which is undesirable. Therefore there is a need for a USB connector with Improved lateral mechanical stability as well.
Additionally, the height of the USB connector above the printed circuit board when the USB connector is mounted vertically is of course greater than when the USB connector is mounted horizontally on the printed circuit board. If the USB connector is mounted on the printed circuit board so as to lie at an angle to the printed circuit board, though that angle may be the same for both a vertically mounted USB connector and a horizontally mounted USB connector, the top edge of the housing of the vertically mounted USB connector will nevertheless project further towards a cable connector opening in a side wall portion of a device in which such USB connector is installed than would a horizontally mounted USB connector simply because of the greater length of the vertical side of the USB connector. As a result, there is a possibility that the USB connector may come into direct contact with such side wall portion of the device, thus generating interference and degrading the electrical connection. Therefore there is a need to eliminate or at least minimize any such leaning of the USB connector when mounting the connection of the USB connector to the printed circuit board.
To further facilitate an understanding of the conventional art, a description will now be given of a conventional USB connector, with reference to FIGS. 1A and 1B. For convenience of explanation, in the drawings the X1-X2 axis represents the lateral or horizontal dimension, the Z1-Z2 axis represents the longitudinal or vertical dimension and the Y1-Y2 axis represents the depth front-to-rear dimension.
FIGS. 1A and 1B are diagrams of a conventional USB connector. In FIG. 1A, the conventional USB connector 1 is shown opposite a cable connector 10 which is attached to the end of a cable. The USB connector 1 is a right-angle type connector, and consists of an insulation panel 2 and a plurality of right-angle contact terminals 3 inserted within a sheet metal housing 4. The sheet metal housing 4 is formed from a single piece of sheet metal folded into a substantially box-like shape. Legs 4a are formed at a rear Y1 side of the sheet metal housing 4.
This USB connector is mounted atop a printed circuit board 15 as shown in FIG. 1B by inserting the legs 4a and the tip portions 3a of the downward-facing tips of the contact terminals 3 into holes 16, 17 in the printed circuit board 15 and soldering them thereto. A cable connector insertion port 5 of the USB connector 1 is open to an opening (not shown in the diagram) in the side of the device. The cable connector 10 passes through this opening in the side of the device and is inserted in and thereby connected to the cable connector insertion port 5 of the USB connector 1.
When mounted, the USB connector is fixed only at the rear Y1 side but not at a front Y2 side at which the cable connector insertion port 5 is formed. The USB connector is therefore not well balanced, and additionally, the cable connector insertion port 5 lacks the requisite stability and rigidity to retain its level position atop the printed circuit board 15.
As a result, when connecting the cable connector 10 the cable connector insertion port 5 of the USB connector may be pushed and separated from the surface of the printed circuit board 15. Moreover, the cable connector insertion port 5 of the housing 4 may be deformed or may widen when wrenching or twisting movements accompany the connection of the cable connector 10.
Additionally, because the legs 4a of the USB connector 1 are positioned only at the rear Y1 side of the USB connector 1, when mounted provisionally the USB connector 1 has a tendency to tilt toward the front due to the force of gravity as shown in FIG. 1B. The USB connector 1 must therefore be made level prior to soldering, a requirement that slows the speed with which the USB connector 1 can be mounted on the printed circuit board 15.